Antarctic elevation drives hemispheric asymmetry in polar lapse-rate climatology and feedback

This is a Preprint and has not been peer reviewed. The published version of this Preprint is available: This is version 2 of this Preprint.


Download Preprint

Supplementary Files

Lily Caroline Hahn , Kyle C Armour , David S Battisti, Aaron Donohoe, Andrew Pauling, Cecilia Bitz


The lapse-rate feedback is the dominant driver of stronger warming in the Arctic than the Antarctic in simulations with increased CO2. While Antarctic surface elevation has been implicated in promoting a weaker Antarctic lapse-rate feedback, the mechanisms in which elevation impacts the lapse-rate feedback are still unclear. Here we suggest that weaker Antarctic warming under CO2 forcing stems from shallower, less intense climatological inversions due to limited atmospheric heat transport above the ice sheet elevation and elevation-induced katabatic winds. In slab ocean model experiments with flattened Antarctic topography, stronger climatological inversions support a stronger lapse-rate feedback and annual-mean Antarctic warming comparable to the Arctic under CO2 doubling. Unlike the Arctic, seasonality in warming over flat Antarctica is mainly driven by a negative shortwave cloud feedback which exclusively dampens summer warming, with a smaller contribution from the winter-enhanced lapse-rate feedback.



Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics



Published: 2020-06-06 19:01

Last Updated: 2020-07-09 23:36

Older Versions

GNU Lesser General Public License (LGPL) 2.1

Add a Comment

You must log in to post a comment.


There are no comments or no comments have been made public for this article.